Thomas sustained an apparent leg injury during Saturday’s 49-24 loss at Iowa State, and underwent surgery this week.
Thomas played in only the Ohio State game last season before an injury cut short his sophomore season.
Thomas, a junior out of Fort Worth Paschal, had been emerging as a possible go-to target for the Frogs early on. He had 121 yards receiving with one touchdown on eight catches this season.
In the SMU game, Thomas finished with 70 yards receiving on four catches. Against Kansas two weeks ago, he had three catches for 44 yards, including a 26-yard TD on the opening drive.
Losing Thomas is another blow to the Frogs’ receiving corps.
TCU has been without Taye Barber and Mikel Barkley much of this season, and TreVontae Hights was sidelined in the KU game with an injury.
The Frogs have the eighth-ranked pass offense in the Big 12, averaging 214.8 yards a game through the air. They have the worst completion percentage in the league at 55.6 percent (90-of-162).
TCU is on a bye this week before traveling to Kansas State on Oct. 19. Kickoff for that game has been set for 1:30 p.m.